Phenotype Characteristics of Patients With Age-Related Macular Degeneration Carrying a Rare Variant in the Complement Factor H Gene

Age-Related Macular Degeneration and Extramacular Drusen: Genetic Associations in the Coimbra Eye Study

Purpose

To explore the association between the genetics of age-related macular degeneration (AMD) and extramacular drusen (EMD) in patients with and without AMD.

Methods

We included 1753 eyes (912 subjects) with phenotypic characterization regarding AMD and EMD. Genetic sequencing and the genetic risk score (GRS) for AMD were performed according to the EYE-RISK consortium methodology. To test for differences in the GRS from EMD cases, AMD cases, and controls, a clustered Wilcoxon rank-sum test was used. The association of AMD, EMD, and the GRS was evaluated using logistic regression models adjusted for age and sex. Individual associations of common risk variants for AMD with EMD were explored.

Results

EMD were found in 755 eyes: 252 (14.4%) with AMD and 503 (28.7%) without. In total, 122 eyes (7.0%) had only AMD, and 876 (50.0%) were controls. EMD were strongly associated with AMD (odds ratio [OR], 3.333; 95% confidence interval [CI], 2.356-4.623; P < 0.001). The GRS was associated with an increased risk of AMD (OR, 1.416; 95% CI, 1.218-1.646; P < 0.001) but not with EMD. Individually, the common risk variants ARMS2 rs10490924 (P = 0.042), C3 rs2230199 (P = 0.042), and CETP rs5817082 (P = 0.042) were associated with EMD, after adjustment for AMD, sex, and age.

Conclusions

We found a strong association between EMD and AMD, suggesting a common pathogenesis. The GRS for AMD was not associated with EMD, but a partially overlapping genetic basis was suggested when assessing individual risk variants. We propose that EMD per se do not represent an increase in the global genetic risk for AMD.

Genetic Aspects of Age-Related Macular Degeneration and Their Therapeutic Potential

Age-related macular degeneration (AMD) is a complex and multifactorial disease, resulting from the interaction of environmental and genetic factors. The continuous discovery of associations between genetic polymorphisms and AMD gives reason for the pivotal role attributed to the genetic component to its development. In that light, genetic tests and polygenic scores have been created to predict the risk of development and response to therapy. Still, none of them have yet been validated. Furthermore, there is no evidence from a clinical trial that the determination of the individual genetic structure can improve treatment outcomes. In this comprehensive review, we summarize the polymorphisms of the main pathogenetic ways involved in AMD development to identify which of them constitutes a potential therapeutic target. As complement overactivation plays a major role, the modulation of targeted complement proteins seems to be a promising therapeutic approach. Herein, we summarize the complement-modulating molecules now undergoing clinical trials, enlightening those in an advanced phase of trial. Gene therapy is a potential innovative one-time treatment, and its relevance is quickly evolving in the field of retinal diseases. We describe the state of the art of gene therapies now undergoing clinical trials both in the field of complement-suppressors and that of anti-VEGF.

Consequences of a Rare Complement Factor H Variant for Age-Related Macular Degeneration in the Amish

Purpose

Genetic variants in the complement factor H gene (CFH) have been consistently implicated in age-related macular degeneration (AMD) risk. However, their functional effects are not fully characterized. We previously identified a rare, AMD-associated variant in CFH (P503A, rs570523689) in 19 Amish individuals, but its functional consequences were not investigated.

Methods

We performed genotyping for CFH P503A in 1326 Amish individuals to identify additional risk allele carriers. We examined differences for age at AMD diagnosis between carriers and noncarriers. In blood samples from risk allele carriers and noncarriers, we quantified (i) CFH RNA expression, (ii) CFH protein expression, and (iii) C-reactive protein (CRP) expression. Potential changes to the CFH protein structure were interrogated computationally with Phyre² and Chimera software programs.

Results

We identified 39 additional carriers from Amish communities in Ohio and Indiana. On average, carriers were younger than noncarriers at AMD diagnosis, but this difference was not significant. CFH transcript and protein levels in blood samples from Amish carriers and noncarriers were also not significantly different. CRP levels were also comparable in plasma samples from carriers and noncarriers. Computational protein modeling showed slight changes in the CFH protein conformation that were predicted to alter interactions between the CFH 503 residue and other neighboring residues.

Conclusions

In total, we have identified 58 risk allele carriers for CFH P503A in the Ohio and Indiana Amish. Although we did not detect significant differences in age at AMD diagnosis or expression levels of CFH in blood samples from carriers and noncarriers, we observed modest structural changes to the CFH protein through in silico modeling. Based on our functional and computational observations, we hypothesize that CFH P503A may affect CFH binding or function rather than expression, which would require additional research to confirm.

Phenotypic Expression of CFH Rare Variants in Age-Related Macular Degeneration Patients in the Coimbra Eye Study

Purpose

To determine the association between rare genetic variants in complement factor H (CFH) and phenotypic features in age-related macular degeneration (AMD) patients from the Coimbra Eye Study (CES).

Methods

AMD patients from the Incidence CES (NCT02748824) underwent ophthalmologic examination and color fundus photography, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence, and near-infrared imaging. Multimodal phenotypic characterization was carried out in a centralized reading center. The coding and splice-site regions of the CFH gene were sequenced through single-molecule molecular inversion probe-based next-generation sequencing in association with the EYE-RISK consortium. Variants with minor allele frequency <0.05 resulting in splice-site or protein change were selected. Differences in phenotypic features between carriers and noncarriers were analyzed using generalized estimated equations logistic regression models, considering intereye correlations.

Results

We included 39 eyes of 23 patients carrying rare CFH variants and 284 eyes of 188 noncarriers. Carrier status was associated with having higher drusen burden in the macula in the inner Early Treatment Diabetic Retinopathy Study circle (odds ratio [OR], 5.44 [95% confidence interval {CI}, 1.61-18.37]; P = 0.006), outer circle (OR, 4.37 [95% CI, 1.07-17.77]; P = 0.04), and full grid (OR, 4.82 [95% CI, 1.13-20.52]; P = 0.033). In SD-OCT, a lower total macular volume and lower inner retinal layers' volume (OR, 0.449 [95% CI, 0.226-0.894]; P = 0.023; OR, 0.496 [95% CI, 0.252-0.979]; P = 0.043) and pigment epithelial detachments (PEDs) (OR, 5.24 [95% CI, 1.08-25.44]; P = 0.04) were associated with carrying a rare CFH variant. Carriers with subretinal drusenoid deposits (SDD) had the rare variant P258L in all cases except one.

Conclusions

We identified in our cohort phenotypic differences between carriers and noncarriers of rare variants in the CFH gene. Carriers had more severe disease, namely superior drusen burden, PEDs, and thinner retinas. The rare variant P258L may be associated with SDD. Carriers are probably at increased risk of progression.

An Update on the Hemodynamic Model of Age-Related Macular Degeneration

PURPOSE

To provide an update on the hemodynamic model of age-related macular degeneration (AMD).

DESIGN

Evidence-based perspective.

METHODS

Review of the literature and experience of the authors.

RESULTS

Choroidal hemodynamics are not the primary cause of AMD as proposed by Ephraim Friedman in 1997. However, evidence is accumulating to suggest that choroidal perfusion is an important environmental influence that contributes to our understanding of disease progression in this complex genetic disorder. Although early and intermediate AMD seem to be influenced to a large extent by the underlying genetics, the asymmetry of disease progression to the later stages of AMD cannot be explained by genetics alone. The progression of disease and the asymmetry of this progression seem to correlate with abnormalities in choroidal perfusion that can be documented by optical coherence tomography. These perfusion abnormalities in the setting of a thickened Bruch's membrane are thought to exacerbate the impaired nutritional exchange between the retinal pigment epithelium and the choriocapillaris. We propose that the genetic susceptibility to develop AMD combined with age-related changes in macular choroidal hemodynamics, such as increasing choriocapillaris perfusion deficits and decreasing choroidal vascular densities, play an important role in disease progression and may help to explain the asymmetry between eyes, particularly in the later stages of AMD.

CONCLUSIONS

This updated hemodynamic model of AMD focuses on disease progression and highlights the importance of age-related changes in the choroidal circulation as a major environmental influence on disease severity in eyes that are genetically susceptible to develop AMD.

Genetic Risk in Families with Age-Related Macular Degeneration

Purpose

To determine the contribution of common and rare genetic risk variants in families with age-related macular degeneration (AMD).

Design

Case-control study.

Participants

A family cohort (355 affected and 342 unaffected family members from 144 families with AMD) and an unrelated case-control cohort (1078 patients, 952 controls), recruited from the European Genetic Database.

Methods

Genetic data of both cohorts were filtered for carriership of rare genetic variants in the coding and splice-site regions of the complement factor H (CFH) and complement factor I (CFI) genes, and 52 AMD-associated variants were extracted for calculation of genetic risk scores (GRS). To compare GRSs between familial and nonfamilial rare CFH and CFI variant carriers and noncarriers and between AMD disease stages, we performed a 2-way analysis of variance, with Bonferroni correction for multiple testing. Within families with AMD carrying rare CFH and CFI variants, we analyzed segregation patterns by calculating the proportion of affected among carriers.

Main Outcome Measures

GRSs and segregation of rare CFH and CFI variants.

Results

We observed higher GRSs in familial versus nonfamilial individuals without rare CFH and CFI variants: mean GRS, 1.76 (standard error [SE], 0.08) versus 0.83 (SE, 0.03; P < 0.001). In 51 of 144 families (35.4%), rare CFH and CFI variants were identified. Within the AMD family cohort, carriers of rare CFH and CFI variants showed lower GRSs compared with noncarriers (mean GRS, 1.05 [SE, 0.23] vs. 1.76 [SE, 0.08]; P = 0.02). The proportion of affected family members with a high GRS was 57.3% (176/307). Of the affected family members with a low or intermediate GRS, 40.0% carried rare CFH or CFI variants. Among carriers of 11 rare CFH or CFI variants, the proportion affected by AMD was more than 75%.

Conclusions

Genetic risk in families with AMD often is attributed to high GRSs based on common variants. However, in part of the families with a low or intermediate GRS, rare CFH and CFI variants contributed to disease development. We recommend computing GRSs and sequencing the CFH and CFI genes in families with AMD, in particular in the light of ongoing gene-specific clinical trials.

Evaluating the Occurrence of Rare Variants in the Complement Factor H Gene in Patients With Early-Onset Drusen Maculopathy

Question

What are the genotypic and phenotypic characteristics of patients with early-onset drusen maculopathy?

Findings

In this case-control study, patients with early-onset drusen maculopathy were frequently carriers of rare genetic variants in the complement factor H gene and were characterized by the presence of a large macular drusen area and lower genetic risk scores compared with patients with age-related macular degeneration.

Meaning

Sequencing of the complement factor H gene is important in considering future treatments targeting the complement system in patients with early-onset drusen maculopathy. Furthermore, the presence of a large macular drusen area supports the severe phenotype in these patients, who may be at high risk of developing geographic atrophy or choroidal neovascularization.

Importance

Early-onset drusen maculopathy (EODM) is a severe disease and can lead to advanced macular degeneration early in life; however, genetic and phenotypic characteristics of individuals with EODM are not well studied.

Objective

To identify genotypic and phenotypic characteristics of individuals with EODM.

Design, Setting, and Participants

This case-control study collected data from the European Genetic Database from September 2004 to October 2019. A total of 89 patients with EODM diagnosed at 55 years or younger and 91 patients with age-related macular degeneration (AMD) diagnosed at 65 years or older were included.

Exposures

Coding regions of CFH, CFI, C3, C9, CFB, ABCA4, PRPH2, TIMP3, and CTNNA1 genes were sequenced, genetic risk scores (GRS) were calculated based on 52 AMD-associated variants, and phenotypic characteristics on color fundus photographs were analyzed comparing patients with EODM and AMD.

Main Outcomes and Measures

GRS, frequency of rare genetic complement variants, and phenotypic characteristics.

Results

This case-control study included 89 patients with EODM (mean [SD] age, 51.8 [8.7] years; 58 [65.2%] were female) and 91 patients with AMD (mean [SD] age, 77.6 [6.1] years; 45 [49.5%] female). At a mean (SD) age of 56.4 (7.3) years, 40 of 89 patients with EODM (44.9%) were affected by geographic atrophy or choroidal neovascularization. A lower GRS was observed in patients with EODM compared with patients with AMD (1.03 vs 1.60; P = .002), and 27 of 89 patients with EODM (30.3%) carried rare variants in the CFH gene compared with 7 of 91 patients with AMD (7.7%). Carriership of a rare CFH variant was associated with EODM (odds ratio, 7.2; 95% CI, 2.7-19.6; P < .001). A large macular drusen area (more than 50% covered with drusen) was observed in patients with EODM (24 of 162 eyes [14.8%]) compared with patients with AMD (9 of 164 eyes [5.5%]) (odds ratio, 4.57; 95% CI, 1.5-14.1; P = .008).

Conclusions and Relevance

A large proportion of patients with EODM in this study carried rare CFH variants, with most of the identified CFH variants clustered in the first 7 complement control protein domains affecting factor H and factor H–like 1. Because EODM frequently leads to advanced macular degeneration at an early age and can result in many years of vision loss, this study supports targeting the complement system and sequencing the CFH gene in patients with EODM to improve genetic counseling and future treatments for AMD.

Systemic complement levels in patients with age-related macular degeneration carrying rare or low frequency variants in the CFH gene

Age-related macular degeneration (AMD) is a major cause of vision loss among the elderly in the Western world. Genetic variants in the complement factor H (CFH) gene are associated with AMD, but the functional consequences of many of these variants are currently unknown. In this study, we aimed to determine the effect of 64 rare and low-frequency variants in the CFH gene on systemic levels of factor H (FH) and complement activation marker C3bBbP using plasma samples of 252 carriers and 159 non-carriers. Individuals carrying a heterozygous nonsense, frameshift or missense variant in CFH presented with significantly decreased FH levels and significantly increased C3bBbP levels in plasma compared to non-carrier controls. FH and C3bBbP plasma levels were relatively stable over time in samples collected during follow-up visits. Decreased FH and increased C3bBbP concentrations were observed in carriers compared to non-carriers of CFH variants among different AMD stages, with the exception of C3bBbP levels in advanced AMD stages, which were equally high in carriers and non-carriers. In AMD families, FH levels were decreased in carriers compared to non-carriers, but C3bBbP levels did not differ. Rare variants in the CFH gene can lead to reduced FH levels or reduced FH function as measured by increased C3bBbP levels. The effects of individual variants in the CFH gene reported in this study will improve the interpretation of rare and low-frequency variants observed in AMD patients in clinical practice.

Family-based exome sequencing identifies rare coding variants in age-related macular degeneration

Genome-wide association studies (GWAS) have identified 52 independent variants at 34 genetic loci that are associated with age-related macular degeneration (AMD), the most common cause of incurable vision loss in the elderly worldwide. However, causal genes at the majority of these loci remain unknown. In this study, we performed whole exome sequencing of 264 individuals from 63 multiplex families with AMD and analyzed the data for rare protein-altering variants in candidate target genes at AMD-associated loci. Rare coding variants were identified in the CFH, PUS7, RXFP2, PHF12 and TACC2 genes in three or more families. In addition, we detected rare coding variants in the C9, SPEF2 and BCAR1 genes, which were previously suggested as likely causative genes at respective AMD susceptibility loci. Identification of rare variants in the CFH and C9 genes in our study validated previous reports of rare variants in complement pathway genes in AMD. We then extended our exome-wide analysis and identified rare protein-altering variants in 13 genes outside the AMD-GWAS loci in three or more families. Two of these genes, SCN10A and KIR2DL4, are of interest because variants in these genes also showed association with AMD in case-control cohorts, albeit not at the level of genome-wide significance. Our study presents the first large-scale, exome-wide analysis of rare variants in AMD. Further independent replications and molecular investigation of candidate target genes, reported here, would assist in gaining novel insights into mechanisms underlying AMD pathogenesis.

Complement in Neurologic Disease

Classic innate immune signaling pathways provide most of the immune response in the brain. This response activates many of the canonical signaling mechanisms identified in peripheral immune cells, despite their relative absence in this immune-privileged tissue. Studies over the past decade have strongly linked complement protein production and activation to age-related functional changes and neurodegeneration. The reactivation of the complement signaling pathway in aging and disease has opened new avenues for understanding brain aging and neurological disease pathogenesis and has implicated cell types such as astrocytes, microglia, endothelial cells, oligodendrocytes, neurons, and even peripheral immune cells in these processes. In this review, we aim to unravel the past decade of research related to complement activation and its numerous consequences in aging and neurological disease.

Genotype- and Phenotype-Based Subgroups in Geographic Atrophy Secondary to Age-Related Macular Degeneration: The EYE-RISK Consortium

PURPOSE

Geographic atrophy (GA) secondary to age-related macular degeneration is considered a single entity. This study aimed to determine whether GA subgroups exist that can be defined by their genotype and phenotype.

DESIGN

Retrospective analysis of cross-sectional data.

PARTICIPANTS

Individuals (196 eyes of 196 patients) 50 years of age or older with GA from the EYE-RISK database.

METHODS

Participants were graded for the presence of each of the following fundus features on color fundus photography: large soft drusen, reticular pseudodrusen (RPD), refractile drusen, hyperpigmentation, location of atrophy (foveal vs. extrafoveal), and multifocal lesions. Genotypes of 33 single nucleotide polymorphisms previously assigned to the complement, lipid metabolism, or extracellular matrix (ECM) pathways and ARMS2 also were included, and genetic risk scores (GRSs) for each of those 3 pathways were calculated. Hierarchical cluster analysis was used to determine subgroups of participants defined by these features. The discriminative ability of genotype, phenotype, or both for each subgroup was determined with 10-fold cross-validated areas under the receiver operating characteristic curve (cvAUCs), and the agreement between predicted and actual subgroup membership was assessed with calibration plots.

MAIN OUTCOME MEASURES

Identification and characterization of GA subgroups based on their phenotype and genotype.

RESULTS

Cluster analyses identified 3 subgroups of GA. Subgroup 1 was characterized by high complement GRS, frequently associated with large soft drusen and foveal atrophy; subgroup 2 generally showed low GRS, foveal atrophy, and few drusen (any type); and subgroup 3 showed a high ARMS2 and ECM GRS, RPD, and extrafoveal atrophy. A high discriminative ability existed between subgroups for the genotype (cvAUC, ≥0.94), and a modest discriminative ability existed for the phenotype (cvAUC, <0.65), with good calibration.

CONCLUSIONS

We identified 3 GA subgroups that differed mostly by their genotype. Atrophy location and drusen type were the most relevant phenotypic features.

Risk factors for progression of age-related macular degeneration

Purpose

Age‐related macular degeneration (AMD) is a degenerative disease of the macula, often leading to progressive vision loss. The rate of disease progression can vary among individuals and has been associated with multiple risk factors. In this review, we provide an overview of the current literature investigating phenotypic, demographic, environmental, genetic, and molecular risk factors, and propose the most consistently identified risk factors for disease progression in AMD based on these studies. Finally, we describe the potential use of these risk factors for personalised healthcare.

Recent findings

While phenotypic risk factors such as drusen and pigment abnormalities become more important to predict disease progression during the course of the disease, demographic, environmental, genetic and molecular risk factors are more valuable at earlier disease stages. Demographic and environmental risk factors such as age and smoking are consistently reported to be related to disease progression, while other factors such as sex, body mass index (BMI) and education are less often associated. Of all known AMD variants, variants that are most consistently reported with disease progression are rs10922109 and rs570618 in CFH, rs116503776 in C2/CFB/SKIV2L, rs3750846 in ARMS2/HTRA1 and rs2230199 in C3. However, it seems likely that other AMD variants also contribute to disease progression but to a lesser extent. Rare variants have probably a large effect on disease progression in highly affected families. Furthermore, current prediction models do not include molecular risk factors, while these factors can be measured accurately in the blood. Possible promising molecular risk factors are High‐Density Lipoprotein Cholesterol (HDL‐C), Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), zeaxanthin and lutein.

Summary

Phenotypic, demographic, environmental, genetic and molecular risk factors can be combined in prediction models to predict disease progression, but the selection of the proper risk factors for personalised risk prediction will differ among individuals and is dependent on their current disease stage. Future prediction models should include a wider set of genetic variants to determine the genetic risk more accurately, and rare variants should be taken into account in highly affected families. In addition, adding molecular factors in prediction models may lead to preventive strategies and personalised advice.

Complement Factor I Gene Polymorphism in a Turkish Age-Related Macular Degeneration Population

OBJECTIVE

Evaluation of Complement Factor I (CFI) rs10033900 and rs2285714 polymorphism frequencies in patients with age-related macular degeneration (AMD) and healthy controls in a Turkish population.

METHODS

A total of 111 eyes of 111 AMD patients and 96 eyes of 96 healthy controls, only one eye of individuals, were included in the study; however, 2 patients' and 4 controls' samples were excluded as analyses could not be performed for rs10033900 polymorphism. The AMD patients and control group (>50 years) lacked corneal, lenticular, vitreal opacity. However, these patients did not have any retinal diseases apart from AMD. Venous blood samples of patients were collected. Central macular thickness, subfoveal choroidal thickness (SCT), presence of reticular drusen, epiretinal membrane, and pigment epithelial detachment were investigated using Spectral-Domain Optical Coherence Tomography, and the largest diameter of atrophic areas measured. Drusen properties were documented from fundus photographs. The lesion width was calculated by using fundus fluorescein angiography.

RESULTS

There was no difference between patient and control groups and polymorphism distributions. The frequency of the CT allele was higher in patients with dry-type AMD with retinal pigment epithelial abnormality (p = 0.041). SCT was significantly thinner in TT allele carriers with rs2285714 polymorphism (p = 0.030). No significant relationship was found between the other parameters and polymorphism distributions. Con-clusion: CFI rs10033900 and rs2285714 polymorphisms in a Turkish population were not associated with AMD.

Genetics and genetic testing for age-related macular degeneration

Considerable advances have been made in our understanding of age-related macular degeneration (AMD) genetics over the past decade. The genetic associations discovered to date are estimated to account for approximately half of AMD heritability, and functional studies of these variants have revealed new insights into disease pathogenesis, leading to the development of potential novel therapies. There is furthermore growing interest in genetic testing for predicting an individual's risk of AMD and offering personalised preventive or therapeutic treatments. We review the progress made so far in AMD genetics and discuss the possible applications for genetic testing.

Association of Rare Predicted Loss-of-Function Variants in Cellular Pathways with Sub-Phenotypes in Age-Related Macular Degeneration

PURPOSE

To investigate the association of rare predicted loss-of-function (pLoF) variants within age-related macular degeneration (AMD) risk loci and AMD sub-phenotypes.

DESIGN

Case-control study.

PARTICIPANTS

Participants of AREDS, AREDS2, and Michigan Genomics Initiative.

METHODS

Whole genome sequencing data were analyzed for rare pLoF variants (frequency <0.1%) in the regions of previously identified 52 independent risk variants known to be associated with AMD. Frequency of the rare pLoF variants in cases with intermediate or advanced AMD was compared with controls. Variants were assigned to the complement, extracellular matrix (ECM), lipid, cell survival, immune system, metabolism, or unknown/other pathway. Associations of rare pLoF variant pathways with AMD sub-phenotypes were analyzed using logistic and linear regression, and Cox proportional hazards models.

MAIN OUTCOME MEASURES

Differences in rare pLoF variant pathway burden and association of rare pLoF variant pathways with sub-phenotypes within the population with AMD were evaluated.

RESULTS

Rare pLoF variants were found in 298 of 1689 cases (17.6%) and 237 of 1518 controls (15.6%) (odds ratio [OR], 1.11; 95% confidence interval [CI], 0.91-1.36; P = 0.310). An enrichment of rare pLoF variants in the complement pathway in cases versus controls (OR, 2.94; 95% CI, 1.49-5.79; P = 0.002) was observed. Within cases, associations between all rare pLoF variants and choroidal neovascularization (CNV) (OR, 1.34; 95% CI, 1.04-1.73; P = 0.023), calcified drusen (OR, 1.33; 95% CI, 1.04-1.72; P = 0.025), higher scores on the AREDS Extended AMD Severity Scale (Standardized Coefficient Beta (β)=0.346 [0.086-0.605], P = 0.009), and progression to advanced disease (hazard ratio, 1.25; 95% CI, 1.01-1.55; P = 0.042) were observed. At the pathway level, there were associations between the complement pathway and geographic atrophy (GA) (OR, 2.17; 95% CI, 1.12-4.24; P = 0.023), the complement pathway and calcified drusen (OR, 3.75; 95% CI, 1.79-7.86; P < 0.001), and the ECM pathway and more severe levels in the AREDS Extended AMD Severity Scale (β = 0.62; 95% CI, 0.04-1.20; P = 0.035).

CONCLUSIONS

Rare pLoF variants are associated with disease progression. Variants in the complement pathway modify the clinical course of AMD and increase the risk of developing specific sub-phenotypes.